Alterations in platelet indices link polycyclic aromatic hydrocarbons toxicity to low-grade inflammation in preschool children. (October 2019)

• Record Type: Journal Article
• Authors: Dai, Yifeng; Huo, Xia; Cheng, Zhiheng; Wang, Qihua; Zhang, Yuling; Xu, Xijin
• Is Part Of: Environment international. Volume 131(2019)
• Publication Date: 2019-10
• Subjects: Polycyclic aromatic hydrocarbons -- Low-grade inflammation -- Platelet -- Child exposure -- E-waste; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2019.105043
• Languages: English
• ISSNs: 0160-4120

Abstract

Abstract: Background: Environmental exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs) can disturb the immune response. However, the effect of PAHs on low-grade inflammation related to platelets in humans is unknown. Objectives: We investigated the association of PAH exposure with low-grade inflammation and platelet parameters in healthy preschoolers. Methods: The present study recruited 239 participants, aged 2–7 years, from an electronic-waste (e-waste)-exposed ( n = 118) and a reference ( n = 121) area. We measured ten urinary PAH metabolites, four types of immune cells and cytokines, and seven platelet parameters, and compared their differences between children from the two groups. Spearman correlation analysis was performed to explore the potential risk factors for PAH exposure and the associations between urinary monohydroxylated PAHs (OH-PAHs) and biological parameters. Associations between urinary PAH metabolites and platelet indices were analyzed using quantile regression models. Mediation analysis was used to understand the relationship between urinary total hydroxynaphthalene (ΣOHNa) and interleukin (IL)-1β through seven platelet indices, as mediator variables. Results: We found higher urinary monohydroxylated PAH (OH-PAH) concentrations, especially 1-hydroxynaphthalene (1-OHNa) and 2-hydroxynaphthalene (2-OHNa), in children from the e-waste-exposed group than in the reference group. These were closely associated with child personal habits and family environment. A decreased lymphocyte ratio and increased pro-inflammatory cytokines, such as gamma interferon-inducible protein (IP)-10 and IL-1β, were found in the e-waste-exposed children. After adjustment for confounding factors, significantly negative correlations were found between levels of mean platelet volume (MPV), platelet distribution width (PDW), platelet-large cell ratio (P-LCR) and ratio of mean platelet volume to platelet count (MPVP) and OH-PAHs. In addition, ΣOHNa was positively associated with IL-1β mediated through MPV, PDW, P-LCR, and ratio of platelet count to lymphocyte count (PLR). Conclusions: Platelet indices were significantly associated with the changes in urinary OH-PAH levels, which may can be regarded as effective biomarkers of low-grade inflammation resulting from low PAH exposure in healthy children. Highlights: Urinary PAH metabolites are increased in the e-waste-exposed preschool children. Elevated urinary PAH metabolites are closely associated with IL-1β and platelet indices. Urinary ΣOHNa is positively associated with IL-1β mediated through platelet indices. Platelet indices may be effective biomarkers of low-grade inflammation under low PAH exposure.